Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-27T19:22:08.123Z Has data issue: false hasContentIssue false
  • English
  • Français

Temporal trends in mortality and effects of by-catch on common bottlenose dolphins, Tursiops truncatus, in southern Brazil

Published online by Cambridge University Press:  09 December 2010

Pedro F. Fruet ,
Paul G. Kinas ,
Kleber G. da Silva ,
Juliana C. Di Tullio ,
Daniele S. Monteiro ,
Luciano Dalla Rosa ,
Sérgio C. Estima  and
Eduardo R. Secchi
Pedro F. Fruet*
Affiliation:
Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande-FURG, RS, Brazil Museu Oceanográfico ‘Prof. Eliézer C. Rios’, Universidade Federal do Rio Grande (FURG), Caixa Postal 379, Rio Grande, RS, Brazil Laboratório de Tartarugas e Mamíferos Marinhos/Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), 96500-970 Caixa Postal 474, Rio Grande, RS, Brazil
Paul G. Kinas
Affiliation:
Laboratório de Estatística Ambiental/Instituto de Matemática, Estatística e Física, Universidade Federal do Rio Grande (FURG), 96200-970, Caixa Postal 474, Rio Grande, RS, Brazil
Kleber G. da Silva
Affiliation:
Núcleo de Educação e Monitoramento Ambiental (NEMA), Rua Maria Araújo, 450, Cassino, Rio Grande, RS, Brazil
Juliana C. Di Tullio
Affiliation:
Pós-Graduação em Oceanografia Biológica, Instituto de Oceanografia, Universidade Federal do Rio Grande-FURG, RS, Brazil Museu Oceanográfico ‘Prof. Eliézer C. Rios’, Universidade Federal do Rio Grande (FURG), Caixa Postal 379, Rio Grande, RS, Brazil Laboratório de Tartarugas e Mamíferos Marinhos/Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), 96500-970 Caixa Postal 474, Rio Grande, RS, Brazil
Daniele S. Monteiro
Affiliation:
Núcleo de Educação e Monitoramento Ambiental (NEMA), Rua Maria Araújo, 450, Cassino, Rio Grande, RS, Brazil
Luciano Dalla Rosa
Affiliation:
Museu Oceanográfico ‘Prof. Eliézer C. Rios’, Universidade Federal do Rio Grande (FURG), Caixa Postal 379, Rio Grande, RS, Brazil
Sérgio C. Estima
Affiliation:
Núcleo de Educação e Monitoramento Ambiental (NEMA), Rua Maria Araújo, 450, Cassino, Rio Grande, RS, Brazil
Eduardo R. Secchi
Affiliation:
Museu Oceanográfico ‘Prof. Eliézer C. Rios’, Universidade Federal do Rio Grande (FURG), Caixa Postal 379, Rio Grande, RS, Brazil Laboratório de Tartarugas e Mamíferos Marinhos/Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), 96500-970 Caixa Postal 474, Rio Grande, RS, Brazil
*
Correspondence should be addressed to: P.F. Fruet, Museu Oceanográfico ‘Prof. Eliézer C. Rios’, Rua Cap. Heitor Perdigão, 10 Caixa Postal 379, Rio Grande, RS, Brazil email: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The mortality of the bottlenose dolphin, Tursiops truncatus, on the southern portion of Rio Grande do Sul State coast was investigated based on 914 beach surveys conducted between 1969 and 2006. A total of 188 stranded bottlenose dolphins were recorded during this period, indicating a 1.8M:1F sex-ratio of those animals sexed (N = 79). Mortality was low in calves, high in juveniles and sub-adults and slightly lower than in adults. The overall mortality was clearly seasonal overlapping with higher fishing efforts in the Patos Lagoon Estuary and adjacent coastal areas, where most individuals washed ashore. Analysis of a continuous 14-year long subset (1993–2006) of the data indicated relatively low levels of mortality between 1995 and 2000 and a marked increase between 2002 and 2005 followed by an apparent drop in 2006. By-catch was responsible for at least 43% of the recorded mortality between 2002 and 2006. Juvenile males were more susceptible to incidental catches. Among females, by-catch of adults represented 75%. Results of a potential biological removal analysis suggest that current levels of fishing-related mortality are unsustainable for the small resident population of bottlenose dolphins that inhabits the Patos Lagoon Estuary, and that this population may be declining.

Keywords

conservationtime series analysissex-ratioTursiops truncatuspotential biological removalRio Grande do Sul
Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 92 , Issue 8: Marine Mammals , December 2012 , pp. 1865 - 1876
Copyright
Copyright © Marine Biological Association of the United Kingdom 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Almeida, H.L.P.S. and D'Incao, F. (1999) Análise do esforço de pesca do Camarão-rosa (Farfantepenaeus paulensis) na Lagoa dos Patos, Brasil. Atlântica 21, 77–92.Google Scholar
Barreto, A.S. (2000) Variação craniana e genética de Tursiops truncatus (Cetacea, Delphinidae) na costa Atlântica da América do Sul. PhD thesis. Universidade Federal do Rio Grande, Rio Grande, RS, Brasil.Google Scholar
Burkhart, S.M. and Slooten, E. (2003) Population viability analysis for Hector's dolphin (Cephalorhynchus hectori): a stochastic population model for local populations. New Zealand Journal of Marine and Freshwater Research 37, 553–566.CrossRefGoogle Scholar
Castello, H.P. and Pinedo, M.C. (1977) Botos na Lagoa dos Patos. Natureza em Revista 12, 46–49.Google Scholar
Caughley, G. (1966) Mortality patterns in mammals. Ecology 47, 906–918.CrossRefGoogle Scholar
Caughley, G. (1977) Analysis of vertebrate populations. New York: Wiley.Google Scholar
CEPERG/IBAMA. (1999) Desembarque de pescado no Rio Grande do Sul: 1996–1998. Rio Grande, Brasil: Ministério do Meio Ambiente, Ocassional Publications.Google Scholar
Chivers, S.J. (2002) Cetacean life history. In Perrin, W.F., Würsig, B. and Thewissen, J.G.M. (eds) Encyclopedia of marine mammals. San Diego, CA: Academic Press, pp. 221–225.Google Scholar
Cockcroft, V.G., Cliff, G. and Ross, G.J.B. (1989) Shark predation on Indian Ocean bottlenose dolphins Tursiops truncatus off Natal, South Africa. South African Journal of Zoology 24, 305–310.CrossRefGoogle Scholar
Cox, T.M., Read, A.J., Barco, S.G., Evans, J., Gannon, D.P., Koopman, H.N., Mclellan, W.A., Murray, K., Nicolas, J., Pabst, D.A., Potter, C.W., Swingle, W.M., Thayer, V.G., Touhey, K.M. and Westgate, A.J. (1998) Documenting the by-catch of harbour porpoises, Phocoena phocoena, in coastal gillnet fisheries from stranded carcasses. Fishery Bulletin 96, 727–734.Google Scholar
D'Agrosa, C., Lennert-Cody, C.E. and Vidal, O. (2000) Vaquita by-catch in Mexico's artisinal gillnet fisheries: driving a small population to extinction. Conservation Biology 14, 1110–1119.CrossRefGoogle Scholar
da Silva, V M.F. and Best, R.C. (1996) Freshwater dolphin/fisheries interaction in the central Amazon (Brazil). Amazoniana 14, 165–175.Google Scholar
Dalla Rosa, L. (1999) Estimativa do tamanho da população de botos, Tursiops truncatus, do estuário da Lagoa dos Patos, RS, a partir da foto-identificação de indivíduos com marcas naturais e da aplicação de modelos de marcação-recaptura. Master's dissertation. Universidade Federal do Rio Grande, Rio Grande, RS, Brasil.Google Scholar
Dalla Rosa, L. and Secchi, E.R. (2007) Killer whale (Orcinus orca) interactions with the tuna and swordfish longline fishery off southern and south-eastern Brazil: a comparison with shark interactions. Journal of the Marine Biological Association of the United Kingdom 87, 135–140.CrossRefGoogle Scholar
Dans, S.L., Koen Alonso, M., Pedraza, S. and Crespo, E.A. (2003) Incidental catch of dolphins in trawling fisheries off Patagonia, Argentina: can populations persist? Ecological Applications 13, 754–762.CrossRefGoogle Scholar
D'Incao, F. (1991) Pesca e biologia de Penaeus paulensis na Lagoa dos Patos, RS. Atlântica 13, 159–168.Google Scholar
Di Tullio, J.C. (2009) Uso do habitat do boto, Tursiops truncatus, no estuário da Lagoa dos Patos e águas costeiras adjacentes, RS, Brasil. Master's dissertation. Universidade Federal do Rio Grande, Rio Grande, RS, Brasil.Google Scholar
Dumont, L.F.C. and D'Incao, F. (in press) By-catch analysis of Argentinean prawn Artemesia longinaris (Decapoda: Penaeidae) in surrounding area of Patos Lagoon, southern Brazil: effects of different rainfall. Journal of the Marine Biological Association of the United Kingdom.Google Scholar
Garcia, A.M., Vieira, J.P. and Winemiller, K.O. (2003) Effects of 1997–1998 El Niño on the dynamics of the shallow-water fish assemblage of the Patos Lagoon Estuary (Brazil). Coastal and Shelf Science 57, 489–500.CrossRefGoogle Scholar
Geraci, J.R. and Lounsbury, V.L. (2005) Marine mammals ashore: a field guide for strandings. 2nd edition. Baltimore, MD: National Aquarium in Baltimore.Google Scholar
Haimovici, M., Castello, J.P. and Vooren, C.M. (1998) Pescarias. In Seeliger, U., Odebrecht, C. and Castello, J.P. (eds) Os ecosistemas costeiro e marinho do extremo sul do Brasil. Rio Grande: Ecoscientia, pp. 205–218.Google Scholar
Hall, M.A. (1998) An ecological view of the tuna–dolphin problem: impacts and trade-offs. Reviews in Fish Biology and Fisheries 8, 1–34.CrossRefGoogle Scholar
Hersh, S.L., Odell, D.K. and Asper, E.D. (1990) Bottlenose dolphin mortality patterns in the Indian/Banana River system of Florida. In Leatherwood, S. and Reeves, R.R. (eds) The bottlenose dolphin. San Diego, CA: Academic Press, pp. 155–164.CrossRefGoogle Scholar
IUCN (2000) IUCN Red List of threatened species. International Union for Conservation of Nature and Natural Resources, Species Survival Commission (www.redlist.org).Google Scholar
Klippel, S., Peres, M.B., Vooren, C.M. and Lamónaca, A.F. (2005). A pesca artesanal na costa da Plataforma Sul. In Vooren, C.M. and Klippel, S. (eds) Ações para a conservação de tubarões e raias no sul do Brasil. Rio Grande: Igaré, pp. 180–197.Google Scholar
Laporta, P. (2009) Abundância, distribuição e uso de habitat do boto, Tursiops truncatus, em Cabo Polonio e La Coronilla, Rocha, Uruguai. Master's dissertation. Universidade Federal do Rio Grande, Rio Grande, RS, Brasil.Google Scholar
Laws, R.M. (1956) Growth and sexual maturity in aquatic mammals. Nature 178, 193–194.CrossRefGoogle Scholar
Manly, B.F.J. and Walshe, K. (1999) The population management plan for the New Zealand sea lion. In Garner, G.W., Amstrup, S.C., Laake, J.L., Manly, B.F.J, McDonald, L.L. and Robertson, D.G. (eds) Marine mammal survey and assessment methods. Rotterdam: Balkema, pp. 271–283.Google Scholar
Mann, J. and Barnett, H. (1999) Lethal tiger shark (Galeocerdo cuvieri) attack on bottlenose dolphin (Tursiops sp.) calf: defense and reactions by the mother. Marine Mammal Science 15, 568–575.CrossRefGoogle Scholar
Mattos, P.H., Dalla Rosa, L. and Fruet, P.F. (2007) Activity budgets and distribution of bottlenose dolphin (Tursiops truncatus) in the Patos Lagoon estuary, southern Brazil. Latin American Journal of Aquatic Mammals 6, 161–169.CrossRefGoogle Scholar
Mattson, M.C., Mullin, K.D., Ingram, Jr G.W. and Hoggard, W. (2006) Age structure and growth of the bottlenose dolphin (Tursiops truncatus) from strandings in the Mississippi sound region of the north-central Gulf of Mexico from 1986 to 2003. Marine Mammal Science 22, 654–666.CrossRefGoogle Scholar
McFee, W.E. and Hopkins-Murphy, S.R. (2002) Bottlenose dolphin (Tursiops truncatus) strandings in South Carolina, 1992–1996. Fishery Bulletin 100, 258–265.Google Scholar
Milner-Gulland, E.J. and Akçakaya, H.R. (2001) Sustainability indices for exploited populations. Trends in Ecology and Evolution 16, 686–692.CrossRefGoogle Scholar
Möller, O.O., Castello, J.P. and Vaz, A.C. (2009) The effect of river discharge and winds on the interannual variability of the pink shrimp Farfantepenaeus paulensis production in Patos Lagoon. Estuaries and Coasts 32, 787–796.CrossRefGoogle Scholar
NMFS (2000) Marine Mammal Stock Assessment Reports. US National Marine Fisheries Service (http://www.nmfs.noaa.gov/prot_res/mammals/sa_rep/sar.html).Google Scholar
Pinedo, M.C. (1986) Mortalidade de Pontoporia blainvillei, Tursiops gephyreus, Otaria flavescens e Arctocephalus australis na costa do Rio Grande do Sul, Brasil, 1976–1983. In Proceedings of Primeira Reunión de Trabajo de Expertos em Mamíferos Acuáticos de América del Sur, August, 25–29, Buenos Aires, pp. 187–199.Google Scholar
Pinedo, M.C. and Polacheck, T. (1999) Trends in franciscana (Pontoporia blainvillei) stranding rates in Rio Grande do Sul, Southern Brazil (1979–1998). Journal of Cetacean Research and Management 1, 179–189.CrossRefGoogle Scholar
Read, A.J. and Wade, P.R. (2000) Status of marine mammals in the United States. Conservation Biology 14, 929–940.CrossRefGoogle Scholar
Read, A.J., Drinker, P. and Northridge, S. (2006) By-catch of marine mammals in the U.S. and global fisheries. Conservation Biology 20, 163–169.CrossRefGoogle Scholar
Reis, E.G. (1992) An assessment of the exploitation of the white croacker Micropogonias furnieri (Pisces, Sciaenidae) by artisanal and industrial fisheries in coastal waters of southern Brazil. PhD thesis. University of East Anglia, Norwich England.Google Scholar
Reis, E.G. and D'Incao, F. (2000) The present status of artisanal fisheries of extreme southern Brazil: an efforts towards community based management. Ocean and Coastal Management 43, 585–595.CrossRefGoogle Scholar
Secchi, E.R., Ott, P.H., Crespo, E.A., Kinas, P.G., Pedraza, S.N. and Bordino, P. (2001) A first estimate of franciscana (Pontoporia blainvillei) abundance off southern Brazil. Journal of Cetacean Research and Management 3, 95–100.CrossRefGoogle Scholar
Secchi, E.R., Ott, P.H. and Danilewicz, D.S. (2003) Effects of fishing by-catch and conservation status of the franciscana dolphin, Pontoporia blainvillei. In Gales, N., Hindell, M. andKirkwood, R. (eds) Marine mammals: fisheries, tourism and management issues. Collingwood, Victoria: CSIRO Publishing, pp. 174–191.Google Scholar
Sergeant, D.E., Caldwell, D.K. and Caldwell, M.C. (1973) Age, growth, and maturity of bottlenosed dolphin (Tursiops truncatus) from northeast Florida. Journal of the Fisheries Research Board of Canada 30, 1009–1011.CrossRefGoogle Scholar
Simões-Lopes, P.C., Fábian, M.E. and Menegheti, J.O. (1998) Dolphin interactions with the mullet artisanal fishing on southern Brazil: a qualitative and quantitative approach. Revista Brasileira de Zoologia 15, 709–726.CrossRefGoogle Scholar
Slooten, E. (1991) Age, growth and reproduction in Hector's dolphins. Canadian Journal of Zoology 69, 1689–1700.CrossRefGoogle Scholar
Stolen, M.K. and Barlow, J. (2003) A model life table for bottlenose dolphins (Tursiops truncatus) from the Indian River Lagoon System, Florida, USA. Marine Mammal Science 19, 630–649.CrossRefGoogle Scholar
Stolen, M.K., Durden, W.N. and Odell, D.K. (2007) Historical synthesis of bottlenose dolphin (Tursiops truncatus) stranding data in the Indian River Lagoon System, Florida, from 1977–2005. Florida Scientist 70, 45–54.Google Scholar
Tyack, P. (1986) Population biology, social behavior and communication in whales and dolphins. Trends in Ecology and Evolution 1, 144–150.CrossRefGoogle ScholarPubMed
Vooren, C.M., Lessa, R.P. and Klippel, S. (2005) Biologia e status de conservação da viola Rhinobatos horkelii. In Vooren, C.M. and Klippel, S. (eds) Ações para a conservação de tubarões e raias no sul do Brasil. Brasil: Igaré, pp. 33–56.Google Scholar
Wade, P.R. (1998) Calculating limits to the allowable human caused mortality of cetaceans and pinnipeds. Marine Mammal Science 14, 1–37.CrossRefGoogle Scholar
Wade, P.R. and Angliss, R.P. (1997) Report of the GAMMS workshop: April 3–5, 1996, Seattle, Washington. NOAA Technical Memorandum NMFS-OPR-12.Google Scholar
Wells, R.S. (2000) Reproduction in wild bottlenose dolphins: overview of patterns observed during a long-term study. In Duffield, D. and Robeck, T. (eds) Bottlenose dolphin reproduction workshop, Silver Springs, June 3–6, 2000, pp. 57–74.Google Scholar
Wells, R.S., Scott, M.D. and Irvine, A.B. (1987) The social structure of free-ranging bottlenose dolphin. In Genoways, H.H. (ed.) Current mammalogy. New York: Plenum Press, pp. 247–306.CrossRefGoogle Scholar
Wells, R.S. and Scott, M.D. (1990) Estimating bottlenose dolphin population parameters from individual identification and capture–release techniques. Reports of the International Whaling Commission (Special Issue 12), 407–415.Google Scholar
Wells, R.S. and Scott, M.D. (1997) Seasonal incidence of boat strikes of bottlenose dolphin near Sarasota, Florida. Marine Mammal Science 13, 475–480.CrossRefGoogle Scholar
Wells, R.S., Rhinehart, H.L., Hanse, L.J., Sweeney, J.C., Townsend, F.I., Stone, R., Casper, D.R., Scott, M.D., Hohn, A.A. and Rowles, T.K. (2004) Bottlenose dolphins as marine ecosystem sentinels: developing a health monitoring system. EcoHealth 1, 246–254.CrossRefGoogle Scholar
Wood, S.N. (2001) mgcv: GAMs and generalized ridge regression for R. R News 1, 20–25.Google Scholar
Zar, J.H. (1999) Biostatistical analysis. 4th edition. Upper Saddle River, NJ: Prentice-Hall, 123 pp.Google Scholar
Zerbini, A. and Kotas, J.E. (1998) A note on cetacean bycatch in pelagic driftnets off Southern Brazil. Reports of the International Whaling Commission 48, 519–524.Google Scholar